J.B.
Yes - it wouldn't be a traditional "with sympathy" card or anything given the amount of time that has passed, but a simple card with a note enclosed would be thoughtful. Just something along the lines of "I recently learned of Mary's passing in 2008. She and I were high school and college friends who lost touch a few years ago, but I always thought fondly of her and was saddened to hear this news. She was a good friend to me for many years and I will miss her and you will be in my thoughts." My brother passed away last year and my parents and I still hear from random people who are just hearing of the news and it's always touching to know that he is remembered.